An echo canceller improved so as to reduce amount of calculation when performing echo cancellation in a communication channel is disclosed, for example, in Japanese Patent Application Kokai (Laid-Open) Publication No. 2003-134005 (Patent Document 1).
In this echo canceller, an input signal from a communication channel is divided into subbands by a decimator and a subband filter. A position where an echo in the subband arises is detected by an echo position detector and a peak detector, and the detection signal is used for controlling the echo canceller.
By the above-mentioned control, the echo canceller is controlled with very small amount of calculation.